diff --git a/modules/azure-openai/src/lib/mappers.ts b/modules/azure-openai/src/lib/mappers.ts
index d6c35be..374091a 100644
--- a/modules/azure-openai/src/lib/mappers.ts
+++ b/modules/azure-openai/src/lib/mappers.ts
@@ -1,29 +1,32 @@
 import {
-  ChatCompletionOptions, ChatCompletionsFunctionToolCall,
+  ChatCompletionOptions,
+  ChatCompletionsFunctionToolCall,
   ChatResponseMessage,
-  ChatRole, ChatRoles,
-  CompletionFinishReason, CompletionFinishReasons,
-  CompletionUsage
-} from "@one-beyond-ai/common";
+  ChatRole,
+  ChatRoles,
+  CompletionFinishReason,
+  CompletionFinishReasons,
+  CompletionUsage,
+} from '@one-beyond-ai/common';
 import {
   CompletionsUsage as AzureCompletionsUsage,
   GetChatCompletionsOptions,
   ChatCompletionsResponseFormat,
   ChatResponseMessage as AzureChatResponseMessage,
-} from "@azure/openai";
+} from '@azure/openai';
 
 export const mapUsage = (usage?: AzureCompletionsUsage): CompletionUsage => {
   return {
     completionTokens: usage?.completionTokens ?? 0,
     promptTokens: usage?.promptTokens ?? 0,
-    totalTokens: usage?.totalTokens ?? 0
+    totalTokens: usage?.totalTokens ?? 0,
   };
-}
+};
 
 export const mapRole = (role: string): ChatRole => {
   if (ChatRoles.includes(role as ChatRole)) return role as ChatRole;
-  return "assistant";
-}
+  return 'assistant';
+};
 
 export const mapMessage = (message?: AzureChatResponseMessage): ChatResponseMessage | undefined => {
   if (!message) {
@@ -33,16 +36,47 @@ export const mapMessage = (message?: AzureChatResponseMessage): ChatResponseMess
     role: mapRole(message.role),
     content: message.content,
     functionCall: message.functionCall,
-    toolCalls: message.toolCalls as unknown as ChatCompletionsFunctionToolCall[] ?? []
+    toolCalls: (message.toolCalls as unknown as ChatCompletionsFunctionToolCall[]) ?? [],
   };
-}
+};
+
+export const mergeToolCalls = (toolCalls: ChatCompletionsFunctionToolCall[], delta: ChatResponseMessage) =>
+  toolCalls.length > 0
+    ? toolCalls.map((toolCall, i) => ({
+        function: {
+          name: toolCall.function.name,
+          arguments: toolCall.function.arguments + (delta.toolCalls[i]?.function.arguments ?? ''),
+        },
+        id: toolCall.id,
+        type: toolCall.type,
+      }))
+    : delta.toolCalls;
+
+export const mapMessageFromStream = (
+  messageAccumulator: ChatResponseMessage | undefined,
+  delta: AzureChatResponseMessage
+): ChatResponseMessage | undefined => {
+  const mappedDelta = mapMessage(delta);
+  if (!mappedDelta) return messageAccumulator;
+  return {
+    role: mappedDelta?.role ?? messageAccumulator?.role,
+    content: messageAccumulator?.content
+      ? messageAccumulator?.content + (mappedDelta?.content ?? '')
+      : mappedDelta?.content ?? '',
+    functionCall: mappedDelta?.functionCall,
+    toolCalls: mergeToolCalls(messageAccumulator?.toolCalls ?? [], mappedDelta),
+  };
+};
 
 export const mapFinishReason = (finishReason: string | null): CompletionFinishReason | null => {
-  if (CompletionFinishReasons.includes(finishReason as CompletionFinishReason)) return finishReason as CompletionFinishReason;
+  if (CompletionFinishReasons.includes(finishReason as CompletionFinishReason))
+    return finishReason as CompletionFinishReason;
   return null;
-}
+};
 
-export const mapResponseFormat = (responseFormat?: ChatCompletionOptions["responseFormat"]): ChatCompletionsResponseFormat | undefined => {
+export const mapResponseFormat = (
+  responseFormat?: ChatCompletionOptions['responseFormat']
+): ChatCompletionsResponseFormat | undefined => {
   switch (responseFormat) {
     case 'json':
       return { type: 'json_object' };
@@ -50,12 +84,12 @@ export const mapResponseFormat = (responseFormat?: ChatCompletionOptions["respon
       return { type: 'text' };
   }
   return undefined;
-}
+};
 
 export const mapChatCompletionOptions = (options?: ChatCompletionOptions): GetChatCompletionsOptions | undefined => {
   if (!options) return undefined;
   return {
     ...options,
     responseFormat: mapResponseFormat(options?.responseFormat),
-  }
-}
+  };
+};